Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 6.171
1.
Cureus ; 16(2): e55117, 2024 Feb.
Article En | MEDLINE | ID: mdl-38558584

Introduction Chronic periodontal diseases can lead to bone defects and tooth loss, making accurate diagnosis essential for treatment. Various methods are used for diagnosing furcation involvement, with clinical examination and cone-beam computed tomography (CBCT) being the most effective. CBCT produces reliable images with submillimeter resolution, revealing marginal bone contours and furcation defects. Limited studies show that CBCT is more precise than clinical detection for diagnosing furcation involvement. Therefore, CBCT technology can be considered as an adjunct method for furcation involvement detection. This study tests the accuracy and efficiency of CBCT and clinical examination in detecting furcation involvement. Material and methods The study included 25 patients (68 molars) with generalized periodontitis of stage II to IV, Grade B and C. Inclusion criteria required at least two intrabony defects with probing depth > 6mm in both jaws and criteria of periodontitis in at least 30% of the teeth present. Results The study compared clinical examination and CBCT readings for measuring maxillary and mandibular teeth furcation involvement. The results show significant differences between clinical and CBCT measurements of maxillary teeth furcation involvement, particularly in specific areas and types of furcation involvement. In contrast, there were significant differences between clinical and CBCT readings for only a few measurements of mandibular teeth furcation involvement. Therefore, the study suggests that CBCT imaging may be beneficial for accurate diagnosis and treatment planning in cases of furcation involvement in maxillary teeth. Conclusion CBCT imaging is a reliable adjunct method for detecting furcation involvement in maxillary teeth, while clinical examination alone may not be sufficient. Therefore, the use of CBCT technology should be considered in cases where accurate detection of furcation involvement is necessary for successful treatment outcomes. However, further studies with larger sample sizes are needed to confirm these findings.

2.
Int J Clin Pediatr Dent ; 17(1): 15-20, 2024 Jan.
Article En | MEDLINE | ID: mdl-38559863

Aim: This study was planned to evaluate and compare the cleaning efficacy of three pediatric rotary files with the standard Protaper adult file system in primary teeth using cone-beam computed tomography (CBCT). Materials and methods: A total of 40 extracted deciduous second molars, with palatal/mesial roots having at least two-thirds of root length and an intact furcation area, were distributed randomly among four groups, with each group containing 10 teeth. Canal preparation of group I (Pro AF Baby Gold), group II (Kedo SG Blue), group III (Prime Pedo), and group IV (Protaper) was done. Pre- and postoperative CBCT images were taken. The volumetric changes of the root canals were assessed and subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) version 16 and R Studio 3.1.1. Volumetric changes within the groups were analyzed using paired t-tests and between the groups using analysis of variance (ANOVA). Results: The comparison of mean volume difference between groups using ANOVA was statistically significant with F = 4.467, p = 0.002. A Tukey post hoc test revealed that group IV was statistically significant compared with groups I (p = 0.033) and III (p = 0.008) but was not statistically significant with group II (p = 0.170). There was no statistically significant difference in volumetric changes within the three pediatric rotary file systems. Conclusion: Protaper removed more dentin than all the pediatric rotary files, but it was not statistically significant over Kedo SG Blue. Among the pediatric rotary files, Kedo SG Blue removed more dentin than Pro AF Baby Gold and Prime Pedo, but they were not statistically significant. How to cite this article: Nainer Chidambaram JV, Jayaprakash J, Arangannal P. Volumetric Analysis of Various Pediatric Rotary Files in the Preparation of Primary Root Canals Using Cone-beam Computed Tomography. Int J Clin Pediatr Dent 2024;17(1):15-20.

3.
J Prosthodont ; 2024 Apr 02.
Article En | MEDLINE | ID: mdl-38566330

Squamous cell carcinoma is a common malignant condition affecting the oral cavity and may involve the surrounding maxillofacial regions. Treatment commonly involves resection of the tumor, followed by prosthetic rehabilitation of the resection defect. This clinical report presents a 62-year-old Asian male patient who had previously undergone surgical resection, resulting in a post-surgical Aramany Class II maxillary defect. The patient's medical history included severe trismus, characterized by restricted mouth opening, as well as a diagnosis of maxillary sinus verrucous squamous cell carcinoma. This report provides a comprehensive account of the rapid fabrication of an interim obturator using digitally assisted dentistry techniques.

4.
Orthod Craniofac Res ; 2024 Apr 02.
Article En | MEDLINE | ID: mdl-38566529

OBJECTIVE: To investigate the changes in condyle-glenoid fossa relationship after maxillary skeletal expansion (MSE) and to verify the correlation between the condyle positional changes and expansion effect. METHODS: In this study, 20 patients (mean age 21.1 ± 5.7 years, 8 male, 12 female) with maxillary transverse deficiency (MTD) were treated with the MSE appliance, which contained molar bands and a expander with four micro-implants. The CBCT images were taken before expansion (T0), after expansion (T1) and after 6 months of maintenance (T2). The posterior TMJ space (PS), superior TMJ space (SS), anterior TMJ space, coronal lateral TMJ space (CLS), coronal medial TMJ space (CMS), condyle axis angle, maxillary basal bone width (BWM), inter-molars width, nasal bone width, molar inclination and molar palatal cusp height (U6H) were measured using Dolphin Imaging. RESULTS: At T1, compared with T0, the PS and SS significantly increased by 0.41 mm (P = .008) and 0.3 mm (P = .007). But only the SS significantly increased by 0.21 mm (P = .025) at T2. There was a significant difference of 0.37 mm (left-right, P = .014) between the left and right SS at T0, but no significant difference at T1 and T2. The increased BMW showed weak positive correlations with the change of PS (P = .015) and CMS (P = .031), and the decreased U6H showed weak negative correlations with the change of PS (P = .015) and CLS (P = .031) at T1. CONCLUSIONS: The use of MSE led to an increase in the SS and PS, which were weakly correlated with BWM and U6H. But this effect in the TMJ space gradually diminished after 6 months of maintenance, and the symmetry of the condyle-fossa relationship was preserved.

5.
J Orthod ; : 14653125241242138, 2024 Apr 01.
Article En | MEDLINE | ID: mdl-38561938

OBJECTIVE: To assess and compare the validity of 2D modified Easy Box and measurement of the Beta angle on standard conventional orthopantomogram (OPG) versus 3D cone-beam computed tomography (CBCT) OPG-constructed view. DESIGN: A retrospective agreement study. METHODS: The aim of this study was to construct an Easy Box on a standard conventional OPG and to validate this novel method by comparing it with the Easy Box method on 3D CBCT. After approval from the Ethics Committee, OPG and CBCT radiographs were obtained for the study from departmental records and five private practices in the same location (Indore, India). The radiographs were selected based on record availability and with written consent from the participants before the commencement of the study. The records were analysed to enable a comparison and to assess the accuracy of Easy Box construction on both 3D CBCT and standard conventional OPG radiographs. The location of the impacted canine within the Easy Box boundaries and the measurement of the Beta angle were determined on both views. RESULTS: A perfect agreement was obtained for the comparison of 3D Easy Box CBCT analysis with 2D modified Easy Box on OPG for impacted maxillary canines (Kappa = 1.0). A Bland-Altman (LoA) analysis showed no proportional bias in the comparison of the Beta angle on 3D and 2D OPG radiographs. CONCLUSION: Beta angle and 2D modified Easy Box on a conventional OPG yield similar results when compared to Easy Box on 3D CBCT OPG-constructed view. The standard OPG was valuable and cost-effective, particularly in the early stages of diagnosis and treatment planning, either as a substitute or when CBCT was unavailable.

6.
Imaging Sci Dent ; 54(1): 49-56, 2024 Mar.
Article En | MEDLINE | ID: mdl-38571773

Purpose: This study evaluated the impact of artifacts generated by metal crowns on the detection of proximal caries lesions in teeth at various distances using cone-beam computed tomography (CBCT). Additionally, the diagnostic impacts of tube current and metal artifact reduction (MAR) were investigated. Materials and Methods: Thirty teeth were arranged within 10 phantoms, each containing 1 first premolar, 1 second premolar, and 1 second molar. A sound first molar (for the control group) or a tooth with a metal crown was placed. Of the 60 proximal surfaces evaluated, 15 were sound and 45 exhibited enamel caries. CBCT scans were acquired using an OP300 Maxio unit (Instrumentarium, Tuusula, Finland), while varying the tube current (4, 8, or 12.5 mA) and enabling or disabling MAR. Five observers assessed mesial and distal surfaces using a 5-point scale. Multi-way analysis of variance was employed for data comparison, with P<0.05 indicating statistical significance. Results: The area under the curve (AUC) varied from 0.40 to 0.60 (sensitivity: 0.28-0.45, specificity: 0.44-0.80). The diagnostic accuracy was not significantly affected by the presence of a metal crown, milliamperage, or MAR (P>0.05). However, the overall AUC and specificity were significantly lower for surfaces near a crown (P<0.05). Conclusion: CBCT-based caries detection was not influenced by the presence of a metal crown, variations in milliamperage, or MAR activation. However, the diagnostic accuracy was low and was further diminished for surfaces near a crown. Consequently, CBCT is not recommended for the detection of incipient caries lesions.

7.
Imaging Sci Dent ; 54(1): 109-113, 2024 Mar.
Article En | MEDLINE | ID: mdl-38571770

A 54-year-old male patient presented for a periodic check-up at the dental clinic. A panoramic radiograph showed bilateral ossification of the stylohyoid ligament with an oval radiopacity on the right side. Cone-beam computed tomography revealed a well-defined, homogenous hyperdense entity from the lower third of the ossified stylohyoid ligament on the right side. The differential diagnosis of osteoma on the stylohyoid chain includes Eagle syndrome and benign tumors of the stylohyoid chain and adjacent structures. Osteoma rarely manifests in the neck. Even more infrequent are tumors originating from the stylohyoid chain, with only a single documented case of osteoma reported in the literature in 1993. Due to the asymptomatic status, no surgical intervention was advised, and the case would be monitored periodically. This case report describes the details of an osteoma that emerged from the stylohyoid chain, marking it as the second recorded occurrence of this highly rare condition.

8.
Imaging Sci Dent ; 54(1): 1-11, 2024 Mar.
Article En | MEDLINE | ID: mdl-38571778

Purpose: This study was conducted to investigate the safety of dental imaging in pregnant women with respect to fetal health. Materials and Methods: Searches were conducted of the PubMed, Scopus, and Web of Science databases in May 2023. The inclusion criteria encompassed cross-sectional and longitudinal studies that focused on the analysis of diagnostic dental imaging in pregnant women, as well as studies utilizing phantoms to simulate imaging examinations. The exclusion criteria consisted of reviews, letters to the editor, book chapters, and abstracts from scientific conferences and seminars. Results: A total of 3,913 articles were identified. Based on a review of the titles and abstracts, 3,892 articles were excluded, leaving 21 articles remaining for full-text review. Of these, 18 were excluded, and 4 additional articles were included as cross-references. Ultimately, 7 articles underwent quantitative-qualitative analysis. Three retrospective studies were focused on pregnant women who underwent dental imaging procedures. The remaining 4 studies utilized female phantoms to simulate imaging examinations and represent the radiation doses absorbed by the uterus or thyroid. Conclusion: Few dental radiology studies have been conducted to determine the safe radiation threshold for pregnant women. Additionally, the reviewed articles did not provide numbers of dental examinations, by type, corresponding to this dose. Dental imaging examinations of pregnant women should not be restricted if clinically indicated. Ultimately, practitioners must be able to justify the examination and should adhere to the "as low as diagnostically acceptable, being indication-oriented and patient-specific" (ALADAIP) principle of radioprotection.

9.
Imaging Sci Dent ; 54(1): 105-107, 2024 Mar.
Article En | MEDLINE | ID: mdl-38571776

The author herein presents an unusual case of eustachian tube calcification masquerading as loose radiopacities in the temporomandibular joints on a panoramic image, creating a diagnostic challenge. The patient, a 72-year-old woman, presented to the dental service for implant treatment to improve her masticatory function. A cone-beam computed tomography scan was performed and reviewed by a board-certified oral and maxillofacial radiologist. The scan showed no evidence of calcifications in the temporomandibular joints; however, it revealed nodular calcifications within the cartilaginous portion of the eustachian tube bilaterally. Additionally, this report briefly reviews the differential diagnosis of calcified loose bodies in the temporomandibular joint and provides information that needs to be reinforced periodically.

10.
Imaging Sci Dent ; 54(1): 71-80, 2024 Mar.
Article En | MEDLINE | ID: mdl-38571783

Purpose: This study aimed to evaluate age-stratified radiographic features in temporomandibular joint osteoarthritis using cone-beam computed tomography. Materials and Methods: In total, 210 joints from 183 patients (144 females, 39 males, ranging from 12 to 88 years old with a mean age of 44.75±19.97 years) diagnosed with temporomandibular joint osteoarthritis were stratified by age. Mandibular condyle position and bony changes (flattening, erosion, osteophytes, subchondral sclerosis, and subchondral pseudocysts in both the condyle and articular eminence, thickening of the glenoid fossa, joint space narrowing, and joint loose bodies) were evaluated through cone-beam computed tomography. After adjusting for sex, the association between age groups and radiographic findings was analyzed using both a multiple regression model and a multinomial logistic regression model (α=0.05). Results: The prevalence of joint space narrowing and protruded condyle position in the glenoid fossa significantly increased with age (P<0.05). The risks of bony changes, including osteophytes and subchondral pseudocysts in the condyle; flattening, erosion, osteophyte, and subchondral sclerosis in the articular eminence; joint loose bodies; and thickening of the glenoid fossa, also significantly rose with increasing age (P<0.05). The number of radiographic findings increased with age; in particular, the increase was more pronounced in the temporal bone than in the mandibular condyle (P<0.05). Conclusion: Increasing age was associated with a higher frequency and greater diversity of bony changes in the temporal bone, as well as a protruded condyle position in the glenoid fossa, resulting in noticeable joint space narrowing in temporomandibular joint osteoarthritis.

11.
Schweiz Arch Tierheilkd ; 166(4): 191-205, 2024 Apr.
Article En | MEDLINE | ID: mdl-38572821

INTRODUCTION: Incisor malocclusion in rabbits (Oryctolagus cuniculus) is a common clinical problem seen in general practice. Given that the growth rate is about 2 mm per week, a lack of wear quickly leads to feeding difficulties and soft tissue injuries. Therefore, pathologically elongated incisors must be shortened every three to six weeks. The goal of this study was to assess the potential adverse effects on dental and periodontal tissues associated with the three most commonly used trimming methods: nail cutter, diamond-coated cutting disc and diamond burr. The left mandibular incisor of 28 healthy New Zealand rabbits was subjected to four trimmings with one of the three cutting methods. After the fattening period, the mandibles were collected and both mandibular incisors were investigated on dental radiographs, micro-computed tomography scans and histological sections. Dental and periodontal tissue changes were evaluated. This study allowed a more accurate statement of the potential short-term adverse effects of the three trimming methods. At the clinical level, the nail cutter caused the formation of an irregular occlusal surface with sharp edges. Both engine-drive methods allowed the attainment of a smooth surface but the disc was less accurate. Histological evaluation revealed that the primary modifications, including coronal fractures, periodontal ligament widening and inflammation, reparative osteodentine, paracementosis and biofilm accumulation, were found in the nail cutter group.


INTRODUCTION: La malocclusion des incisives chez le lapin (Oryctolagus cuniculus) est un problème clinique courant en médecine générale. Étant donné que le taux de croissance est d'environ 2 mm par semaine, un manque d'usure entraîne rapidement des difficultés d'alimentation et des lésions des tissus mous. Par conséquent, les incisives pathologiquement trop longues doivent être raccourcies toutes les trois à six semaines. L'objectif de cette étude était d'évaluer les effets négatifs potentiels sur les tissus dentaires et parodontaux associés aux trois méthodes de taille les plus couramment utilisées: le coupeongles, le disque de coupe diamanté et la fraise diamantée. L'incisive mandibulaire gauche de 28 lapins néo-zélandais en bonne santé a été soumise à quatre tailles avec l'une des trois méthodes de coupe. Après la période d'engraissement, les mandibules ont été prélevées et les deux incisives mandibulaires ont été examinées sur des radiographies dentaires, des examens micro-tomodensitométriques et des coupes histologiques. Les modifications des tissus dentaires et parodontaux ont été évaluées. Cette étude a permis de mieux cerner les effets indésirables potentiels à court terme des trois méthodes de coupe. Au niveau clinique, le coupe-ongles a entraîné la formation d'une surface occlusale irrégulière avec des bords tranchants. Les deux autres méthodes de taille permettent d'obtenir une surface lisse, mais le disque est moins précis. L'évaluation histologique a révélé que les modifications primaires, y compris les fractures coronaires, l'élargissement et l'inflammation du ligament parodontal, l'ostéodentine réparatrice, la paracémentose et l'accumulation de biofilm, ont été trouvées dans le groupe coupe-ongles.


Incisor , Mandible , Rabbits , Animals , Incisor/diagnostic imaging , Incisor/surgery , X-Ray Microtomography , Mandible/diagnostic imaging , Mandible/surgery
12.
Orthod Craniofac Res ; 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38577813

OBJECTIVES: The primary objective of this study was to assess the validity of the KPG index in predicting the difficulty of treatment involving impacted maxillary canines. The secondary objective was to assess the reliability and reproducibility of the index. MATERIALS AND METHODS: A retrospective study was conducted on 96 maxillary impacted canines (MIC) in 60 patients aged 13-35 years. Cone-beam computed tomography (CBCT) scans were used to predict the treatment difficulty of MIC using the KPG index. Patient case files were assessed for the actual difficulty encountered in treating MIC. Cohen's kappa correlation coefficient was used for intra-observer reliability and Kendell's W test was used for inter-observer reliability. Spearman's correlation coefficient test was used to assess the correlation between predicted and actual treatment. RESULTS: Easy and moderately difficult cases exhibited a moderate correlation between actual and predicted treatment outcomes, whereas difficult cases displayed a weak correlation. The perfect correlation was observed exclusively in extremely difficult cases. The intra-observer reliability for assessing CBCT scans using the KPG guide was found to be 0.88, and the inter-rater reliability was 0.94. CONCLUSION: The KPG index displayed 87%, 71%, 50% and 100% validity in easy, moderately difficult, difficult, and extremely difficult cases, respectively. This index showed good reliability and reproducibility. However, it is imperative to consider a multitude of other factors, including the patient's age, presence of associated root resorption in adjacent teeth, and duration of treatment, to make an informed decision between surgical exposure and extraction.

13.
J Pharm Bioallied Sci ; 16(Suppl 1): S886-S888, 2024 Feb.
Article En | MEDLINE | ID: mdl-38595393

Background: Dental implant surgery has become a widely accepted method for replacing missing teeth. However, the success of dental implant procedures can be influenced by various factors, including the quality of preoperative planning and assessment. Cone beam computed tomography (CBCT) imaging provides valuable insights into a patient's oral anatomy, but accurately predicting implant success remains a challenge. Materials and Methods: In this randomized controlled trial (RCT), a cohort of 150 patients requiring dental implants was randomly divided into two groups: an artificial intelligence (AI)-assisted group and a traditional assessment group. Preoperative CBCT images of all patients were acquired and processed. The AI-assisted group utilized a machine learning model trained on historical data to assess implant success probability based on CBCT images, while the traditional assessment group relied on conventional methods and clinician expertise. Key parameters such as bone density, bone quality, and anatomical features were considered in the AI model. Results: After the completion of the study, the AI-assisted group demonstrated a significantly higher implant success rate, with 92% of implants successfully integrating into the bone compared to 78% in the traditional assessment group. The AI model showed an accuracy of 87% in predicting implant success, whereas traditional assessment methods achieved an accuracy of 71%. Additionally, the AI-assisted group had a lower rate of complications and required fewer postoperative interventions compared to the traditional assessment group. Conclusion: The AI-assisted approach significantly improved implant success rates and reduced complications, underscoring the importance of incorporating AI into the dental implant planning process.

14.
J Pharm Bioallied Sci ; 16(Suppl 1): S951-S954, 2024 Feb.
Article En | MEDLINE | ID: mdl-38595463

Cemento-osseous dysplasia is a subgroup of fibro-osseous dysplasia commonly invading the tooth-bearing regions of the mandible quite often. These bony pathologies are asymptomatic and are seen on radiographs as an incidental finding. Accurate diagnosis of periapical cemento-osseous dysplasia is very crucial as it will help in the proper management of the patient as the incorrect diagnosis can lead to the unnecessary endodontic treatment of the concerned teeth as it may be misdiagnosed as a periapical pathology. We describe a case of periapical cemento-osseous dysplasia in which a 52-year-old woman had been experiencing discomfort in the right mental area of her mandible for the previous 6 months and had finally sought help at the outpatient department. This case study aims to highlight the significance of making an accurate diagnosis of cemento-osseous dysplasias in the tooth-bearing area.

15.
J Pharm Bioallied Sci ; 16(Suppl 1): S871-S873, 2024 Feb.
Article En | MEDLINE | ID: mdl-38595528

Background: In the field of endodontics, accurate diagnosis is pivotal for successful treatment outcomes. This randomized controlled trial (RCT) explores the potential of cone-beam computed tomography (CBCT) as a tool to enhance diagnostic accuracy in endodontic procedures. Materials and Methods: An RCT was conducted with a sample of 120 patients presenting with endodontic issues. The patients were divided into two groups: Group A received traditional two-dimensional radiography, while group B underwent CBCT scans. The diagnostic accuracy was assessed by comparing the radiographic findings with the clinical evaluation by experienced endodontists. Results: The results indicated a significant improvement in diagnostic accuracy in the CBCT group (group B) with an arbitrary value of 88% accuracy, compared with the traditional radiography group (group A) with only 65% accuracy. The CBCT group showed a clearer visualization of root canal anatomy, periapical lesions, and the presence of additional canals, contributing to the enhanced diagnostic capability. Conclusion: This RCT demonstrates that CBCT significantly enhances diagnostic accuracy in endodontics compared with traditional two-dimensional radiography. The improved visualization of root canal anatomy and periapical regions allows for more precise treatment planning, ultimately leading to better treatment outcomes.

16.
J Pharm Bioallied Sci ; 16(Suppl 1): S513-S515, 2024 Feb.
Article En | MEDLINE | ID: mdl-38595619

Background: Accurate assessment of impacted canines is crucial for successful treatment planning. Radiographic techniques like Cone Beam Computed Tomography (CBCT) and Panoramic Radiography are commonly used, but their comparative accuracy remains under scrutiny. Materials and Methods: In this study, 50 patients diagnosed with impacted canines were enrolled. Both CBCT and Panoramic Radiography images were obtained for each patient using standard protocols. Two experienced dentists independently analyzed the images to determine the position of impacted canines and their relationship with neighboring structures. Results: The findings of this study revealed that CBCT provided superior accuracy in assessing the position of impacted canines compared to Panoramic Radiography. Specifically, CBCT demonstrated a mean accuracy rate of 89.5%, while Panoramic Radiography showed a mean accuracy rate of 72.3%. Moreover, CBCT allowed for better visualization of impacted canine angulation, depth, and spatial orientation. Panoramic Radiography, on the other hand, displayed limitations in precisely identifying the impacted canine's position. Conclusion: The study's outcomes underscore the higher accuracy of CBCT over Panoramic Radiography in the preoperative assessment of impacted canines. CBCT's detailed imaging provides valuable insights for treatment planning, potentially leading to improved surgical outcomes. Although CBCT entails greater radiation exposure and cost, its benefits in accurate diagnosis and treatment planning justify its use in cases of impacted canines.

17.
J Pharm Bioallied Sci ; 16(Suppl 1): S380-S382, 2024 Feb.
Article En | MEDLINE | ID: mdl-38595630

Objective: Using cone beam computed tomography (CBCT), this study compared three rotary file systems-XP Endoshaper, Hyflex CM, and K3 XF-for centering, canal transportation, and root canal area growth. Materials and Methods: The rotating file system randomly separated 60 removed human mandibular molars into three groups (n = 20). Manufacturer-recommended root canal instrumentation was done. Specialized software examined pre- and post-instrumentation CBCT scans. Centering ability was measured by canal transportation and root canal area expansion at different levels from the apex. Results: The Hyflex CM file system had the best centering and the least canal transit at all levels (P < 0.05). XP Endoshaper increased the root canal area the most (P < 0.05). The K3 XF file system had average centering and canal transfer results. Conclusion: The Hyflex CM system centered well, whereas the XP Endoshaper system increased the root canal area the most. The clinical context and therapeutic goals should determine the rotating file system.

18.
J Vasc Interv Radiol ; 2024 Apr 08.
Article En | MEDLINE | ID: mdl-38599280

PURPOSE: To evaluate the performance of a prototype flexible transbronchial cryoprobe compared to percutaneous transthoracic cryoablation and to define cone-beam CT (CBCT) imaging and pathology cryolesion features in an in vivo swine model. METHODS: Transbronchial cryoablation was performed with a prototype flexible cryoprobe (3 central and 3 peripheral lung ablations in 3 swine) and compared to transthoracic cryoablation performed with a commercially available rigid cryoprobe (2 peripheral lung ablations in 1 swine). Procedural time and cryoablation success rates for endobronchial navigation and cryoneedle deployment were measured. Intraoperative CBCT imaging features of cryolesions were characterized and correlated with gross and H&E-stained sections of the explanted cryolesions. RESULTS: The flexible cryoprobe was successfully navigated and delivered to each target through a steerable guiding sheath (6/6). At 4 min post ablation, 5/6 transbronchial and 2/2 transthoracic cryolesions were visible on CBCT. The volumes on CBCT images were 55.5±8.0 cm3 for central transbronchial ablations (n=2), 72.5±8.1 cm3 for peripheral transbronchial ablations (n=3), and 79.5±11.6 cm3 for peripheral transthoracic ablations (n=2). Pneumothorax developed in one animal post transbronchial ablation and during ablation in the transthoracic cryoablation. Images of cryoablation zones on CBCT correlated well with the matched gross and histopathology sections of the cryolesions. CONCLUSIONS: Transbronchial cryoablation with a flexible cryoprobe, delivered through a steerable guiding sheath, is feasible. Transbronchial cryoablation zones are imageable with CBCT with gross and histopathology similar to transthoracic cryoablation.

19.
Phys Med Biol ; 2024 Apr 09.
Article En | MEDLINE | ID: mdl-38593826

OBJECTIVE: Newer cone-beam computed tomography (CBCT) imaging systems offer reconstruction algorithms including metal artifact reduction (MAR) and extended field-of-view (eFoV) techniques to improve image quality. In this study a new CBCT imager, the new Varian HyperSight CBCT, is compared to fan-beam CT and two CBCT imagers installed in a ring-gantry and C-arm linear accelerator, respectively. Approach: The image quality was assessed for HyperSight CBCT which uses new hardware, including a large-size flat panel detector, and improved image reconstruction algorithms. The decrease of metal artifacts was quantified (structural similarity index measure (SSIM) and root-mean-squared error (RMSE)) when applying MAR reconstruction and iterative reconstruction for a dental and spine region using a head-and-neck phantom. The geometry and CT number accuracy of the eFoV reconstruction was evaluated outside the standard field-of-view (sFoV) on a large 3D-printed chest phantom. Phantom size dependency of CT numbers was evaluated on three cylindrical phantoms of increasing diameter. Signal-to-noise (SNR) and contrast-to-noise (CNR) were quantified on an abdominal phantom. Main results: In phantoms with streak artifacts, MAR showed comparable results for HyperSight CBCT and CT, with MAR increasing the SSIM (0.97 to 0.99) and decreasing the RMSE (62 HU to 55 HU) compared to iterative reconstruction without MAR. In addition, HyperSight CBCT showed better geometrical accuracy in the eFoV than CT (Jaccard Conformity Index increase of 0.02-0.03). However, the CT number accuracy outside the sFoV was lower than for CT. The maximum CT number variation between different phantom sizes was lower for the HyperSight CBCT imager (~100HU) compared to the two other CBCT imagers (~200HU), but not fully comparable to CT (~50HU). Significance: This study demonstrated the imaging performance of the new HyperSight CBCT imager and the potential of applying this CBCT system in more advanced scenarios by comparing the quality against fan-beam CT.

20.
J Endod ; 2024 Apr 06.
Article En | MEDLINE | ID: mdl-38588977

INTRODUCTION: Pathological conditions such as internal root resorption (IRR) may complicate root canal filling. This study aimed to evaluate and compare the obturation quality by measuring the percentage of obturation volume (POV) in root canals with artificial IRR obturated with different materials and techniques using cone beam computed tomography (CBCT). METHODS: Forty single canal extracted mandibular premolars were decoronated to standardize their length to 14mm. Following instrumentation, the roots were cut horizontally, and artificial IRR cavities were made at the level of 7mm from the apex. The root halves were joined using cyanoacrylate adhesive. The samples were randomly assigned to four groups (n = 10), and the canals were filled as follows: Single-cone technique (SC), bulk-fill Bio-C Sealer (BF), Bio-C Repair for the coronal and middle third (BCR) +cold lateral condensation technique (CLC) for the apical third and continuous wave compaction technique (CWC). The pre-and post-obturation volumes and the POV were measured in the total canal and for the apical, middle, and coronal thirds separately using CBCT and Mimics Medical software. The results were analyzed statistically using one-way ANOVA and Tukey HSD test, and statistical significance was set at p<0.05. RESULTS: BF group resulted in significantly lower total, coronal, middle and apical POV values compared to SC, BCR+ CLC, and CWC groups (p < 0.05), respectively. Also, at the apical third, the BCR+ CLC group showed significantly lower POV than the SC and CWC groups (P<0.05), respectively. The intra-group comparison showed that BF and BCR+ CLC groups had a significantly lower POV in the apical third compared to the middle third (p<0.05). Conversely, the CWC group had a significantly higher apical POV than the middle third (p<0.05). CONCLUSIONS: The maximum POV was obtained using the CWC technique, Bio-C Repair, and SC technique with Bio-C Sealer, making their application in IRR more preferable than the BF Bio-C Sealer.

...